(19)
(11) EP 2 920 593 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
25.06.2025 Bulletin 2025/26

(21) Application number: 13792959.2

(22) Date of filing: 14.11.2013
(51) International Patent Classification (IPC): 
G01N 33/49(2006.01)
G01N 33/574(2006.01)
(52) Cooperative Patent Classification (CPC):
G01N 33/49; G01N 33/57407
(86) International application number:
PCT/GB2013/053005
(87) International publication number:
WO 2014/076480 (22.05.2014 Gazette 2014/21)

(54)

METHODS OF DIAGNOSING PROLIFERATIVE DISORDERS

VERFAHREN ZUR DIAGNOSE PROLIFERATIVER ERKRANKUNGEN

PROCÉDÉ DE DIAGNOSTIC DE TROUBLES PROLIFÉRATIFS


(84) Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30) Priority: 15.11.2012 GB 201220573

(43) Date of publication of application:
23.09.2015 Bulletin 2015/39

(60) Divisional application:
16187778.2 / 3118624

(73) Proprietor: University of Lancashire
Lancashire PR1 2HE (GB)

(72) Inventors:
  • BAKER, Matthew James
    Lytham St Annes FY8 5TE (GB)
  • ABEL, Peter
    Southport PR8 3LP (GB)
  • LEA, Robert William
    Longton Preston PR4 5YJ (GB)

(74) Representative: HGF 
HGF Limited 1 City Walk
Leeds LS11 9DX
Leeds LS11 9DX (GB)


(56) References cited: : 
EP-A1- 2 299 259
US-A1- 2011 027 797
US-A1- 2012 064 529
WO-A2-2011/151825
US-A1- 2011 027 797
US-A1- 2012 064 529
   
  • AYSEGUL ILHAN-MUTLU ET AL: "Exploratory investigation of eight circulating plasma markers in brain tumor patients", NEUROSURGICAL REVIEW, SPRINGER, BERLIN, DE, vol. 36, no. 1, 5 July 2012 (2012-07-05), pages 45 - 56, XP035159037, ISSN: 1437-2320, DOI: 10.1007/S10143-012-0401-6
  • XU BAOGANG J ET AL: "Identification of blood protein biomarkers that aid in the clinical assessment of patients with malignant glioma", INTERNATIONAL JOURNAL OF ONCOLOGY, SPANDIDOS: ATHENS, GR, vol. 40, no. 6, 1 June 2012 (2012-06-01), pages 1995 - 2003, XP009162919, ISSN: 1791-2423, DOI: 10.3892/IJO.2012.1355
  • K RAE ET AL: "Follistatin serum concentrations during full-term labour in women significant differences between spontaneous and induced labour", REPRODUCTION, vol. 134, no. 5, 26 October 2007 (2007-10-26), GB, pages 705 - 711, XP055306869, ISSN: 1470-1626, DOI: 10.1530/REP-07-0208
  • P. SREEKANTHREDDY ET AL: "Identification of Potential Serum Biomarkers of Glioblastoma: Serum Osteopontin Levels Correlate with Poor Prognosis", CANCER EPIDEMIOLOGY, BIOMARKERS AND PREVENTION., vol. 19, no. 6, 1 June 2010 (2010-06-01), US, pages 1409 - 1422, XP055306880, ISSN: 1055-9965, DOI: 10.1158/1055-9965.EPI-09-1077
  • D F ZHANG ET AL: "Expression of activin A and follistatin in glioblastoma and their effects on U87 in vitro", THE JOURNAL OF INTERNATIONAL MEDICAL RESEARCH, 1 July 2010 (2010-07-01), England, pages 1343 - 1353, XP055306883, Retrieved from the Internet <URL:http://imr.sagepub.com/content/38/4/1343.full.pdf> [retrieved on 20160928]
  • AYSEGUL ILHAN-MUTLU ET AL: "Exploratory investigation of eight circulating plasma markers in brain tumor patients", NEUROSURGICAL REVIEW, SPRINGER, BERLIN, DE, vol. 36, no. 1, 5 July 2012 (2012-07-05), pages 45 - 56, XP035159037, ISSN: 1437-2320, DOI: 10.1007/S10143-012-0401-6
  • XU BAOGANG J ET AL: "Identification of blood protein biomarkers that aid in the clinical assessment of patients with malignant glioma", INTERNATIONAL JOURNAL OF ONCOLOGY, SPANDIDOS: ATHENS, GR, vol. 40, no. 6, 1 June 2012 (2012-06-01), pages 1995 - 2003, XP009162919, ISSN: 1791-2423, DOI: 10.3892/IJO.2012.1355
  • K RAE ET AL: "Follistatin serum concentrations during full-term labour in women significant differences between spontaneous and induced labour", REPRODUCTION, vol. 134, no. 5, 26 October 2007 (2007-10-26), GB, pages 705 - 711, XP055306869, ISSN: 1470-1626, DOI: 10.1530/REP-07-0208
  • P. SREEKANTHREDDY ET AL: "Identification of Potential Serum Biomarkers of Glioblastoma: Serum Osteopontin Levels Correlate with Poor Prognosis", CANCER EPIDEMIOLOGY, BIOMARKERS AND PREVENTION., vol. 19, no. 6, 1 June 2010 (2010-06-01), US, pages 1409 - 1422, XP055306880, ISSN: 1055-9965, DOI: 10.1158/1055-9965.EPI-09-1077
  • D F ZHANG ET AL: "Expression of activin A and follistatin in glioblastoma and their effects on U87 in vitro", THE JOURNAL OF INTERNATIONAL MEDICAL RESEARCH, 1 July 2010 (2010-07-01), England, pages 1343 - 1353, XP055306883, Retrieved from the Internet <URL:http://imr.sagepub.com/content/38/4/1343.full.pdf> [retrieved on 20160928]
  • POUNEH KERMANI ET AL: "BDNF: A Newly Described Mediator of Angiogenesis", 1 May 2007 (2007-05-01), XP055392322, Retrieved from the Internet <URL:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2268985/pdf/nihms-23333.pdf> [retrieved on 20170719]
  • XIN ZHOU ET AL: "Conceptual and methodological issues relevant to cytokine and inflammatory marker measurements in clinical research", PUBLISHED IN FINAL EDITED FORM AS: CURR OPIN CLIN NUTR METAB CARE, 1 September 2010 (2010-09-01), pages 541 - 547, XP055756364, Retrieved from the Internet <URL:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2955626/pdf/nihms243735.pdf> [retrieved on 20201203], DOI: 10.1097/MCO
  • LENG S X ET AL: "ELISA and multiplex technologies for cytokine measurement in inflammation and aging research", vol. 63, no. 8, 1 August 2008 (2008-08-01), pages 879 - 884, XP008154409, ISSN: 1079-5006, Retrieved from the Internet <URL:http://biomedgerontology.oxfordjournals.org/content/63/8/879.abstract> DOI: 10.1093/GERONA/63.8.879
  • LUNDBLAD R: "ISPUB Considerations for the Use of Blood Plasma and Serum for Proteomic Analysis", THE INTERNET JOURNAL OF GENOMICS AND PROTEOMICS, vol. 1, no. 2, 1 January 2003 (2003-01-01), pages 1 - 8, XP055756353, Retrieved from the Internet <URL:https://print.ispub.com/api/0/ispub-article/3649>
  • KHANMOHAMMADI, M., ET AL: "Cancer diagnosis by discrimination between normal and malignant human blood samples using attenuated total reflectance-Fourier transform infrared spectroscopy", CANCER INVEST., vol. 25, no. 6, September 2007 (2007-09-01), pages 397 - 404, XP009175260
  • PAN, Q-H., ET AL: "Investigation on Glioma Using FT-mid-IR Spectroscopy", CHEMICAL JOURNAL OF CHINESE UNIVERSITIES, vol. 33, no. 8, 10 August 2012 (2012-08-10), pages 1703 - 1707, XP002718133
  • MOHAMMADREZA KHANMOHAMMADI ET AL: "Application of Linear Discriminant Analysis and Attenuated Total Reflectance Fourier Transform Infrared Microspectroscopy for Diagnosis of Colon Cancer", PATHOLOGY & ONCOLOGY RESEARCH ; OFFICIAL JOURNAL OF THE ARÃ NYI LAJOS FOUNDATION, SPRINGER NETHERLANDS, DORDRECHT, vol. 17, no. 2, 31 December 2010 (2010-12-31), pages 435 - 441, XP019902573, ISSN: 1532-2807, DOI: 10.1007/S12253-010-9326-Y
  • JAMES R. HANDS ET AL: "Investigating the rapid diagnosis of gliomas from serum samples using infrared spectroscopy and cytokine and angiogenesis factors", ANALYTICAL AND BIOANALYTICAL CHEMISTRY, vol. 405, no. 23, 7 July 2013 (2013-07-07), pages 7347 - 7355, XP055094189, ISSN: 1618-2642, DOI: 10.1007/s00216-013-7163-z
   
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

FIELD OF THE INVENTION



[0001] The present invention relates to a method and a diagnostic system for diagnosing glioma.

BACKGROUND OF THE INVENTION



[0002] Proliferative disorders, such as cancer, are caused by uncontrolled and unregulated cellular proliferation. Such cellular proliferation can lead to the formation of tumours in the relevant subjects.

[0003] Typically, tumours, such as brain tumours, are initially clinically identified within a subject by way of various well known pre-screening imaging techniques, such as computed tomography (CT), magnetic resonance imaging (MRI), X-Rays, and positron emission tomography (PET). Such imaging techniques are, however, expensive to deploy given the high cost of both the equipment itself and the human resources required to operate it. Some such imaging techniques require complex operation by highly qualified professionals, and some require time consuming analysis before conclusions can be drawn. Moreover, such techniques seldom, if ever, distinguish between benign and malignant tumours. As such, a final biopsy is always required to confirm the malignancy or benignity of a given tumour.

[0004] Biopsies require invasive surgery to extract a relevant tissue sample. In the case of brain tumours, biopsies generally require drilling into the subject's skull, which is a highly dangerous and skilled surgical operation. The subject having undergone such a biopsy is then typically hospitalised for two to three days, which presents an undesirable care burden. Once the biopsy has been successfully performed, it can take a significant period of time before the malignancy or benignity of the relevant tumour is actually determined.

[0005] It is therefore highly desirable to provide a pre-screening tool that is cost-effective, requires minimal human resource and skill to operate, and does not involve time consuming analysis. It is moreover desirable to provide a pre-screening technique that facilitates relatively fast determination of malignancy or benignity of tumours with a reasonably high degree of accuracy, and without the drawbacks inherent with biopsies.

[0006] In recent times, various biomarkers within the blood have been identified as useful indicators of particular diseases. For instance, cytokines, chemokines, and growth factors are cell signalling proteins that mediate a range of physiological responses, and are associated with various diseases. Such molecules are generally detected by either bioassay or immunoassay, both of which can be time consuming given that often only one analyte may be analysed at a time. However, in more recent times, magnetic bead-based multiplex assays designed to measure multiple cytokines, chemokines, and growth factors in diverse matrices like serum, plasma, and tissue culture supernatants, have become more readily available with kits such as Bio-Plex Pro (see Bio-Plex Pro Assay Handbook - http://www.bio-rad.com/webroot/web/pdf/lsr/literature/10014905.pdf). However, the complexities associated with the correlation of particular biomarkers with particular diseases has retarded developments in the medical diagnostics field, and such correlations are inherently unpredictable at present. Moreover, such assaying still requires a reasonable level of skill, and such assays also destroy the sample in question such that repeat assays on the same sample are not possible. Validation of results is thus more difficult.

[0007] AYSEGUL ILHAN-MUTLU ET AL: "Exploratory investigation of eight circulating plasma markers in brain tumor patients", NEUROSURGICAL REVIEW, SPRINGER, BERLIN, DE, vol. 36, no. 1, 5 July 2012 (2012-07-05), pages 45 - 56, XP035159037, ISSN: 1437-2320, DOI: 10.1007/S10143-012-0401-6, relates to investigations of eight circulating plasma markers in brain tumor patients.

[0008] XU BAOGANG J ET AL: "Identification of blood protein biomarkers that aid in the clinical assessment of patients with malignant glioma", INTERNATIONAL JOURNAL OF ONCOLOGY, SPANDIDOS: ATHENS, GR, vol. 40, no. 6, 1 June 2012 (2012-06-01), pages 1995 - 2003, XP009162919, ISSN: 1791-2423, DOI: 10.3892/IJO.2012.1355, relates to identification of blood protein biomarkers in the clinical assessment of malignant glioma.

[0009] US20110027797A1 (Kumaravel Somasundaram) relates to methods of diagnosing higher- and lower-grade Astrocytoma using biomarkers.

[0010] K RAE ET AL: "Follistatin serum concentrations during full-term labour in women significant differences between spontaneous and induced labour", REPRODUCTION, vol. 134, no. 5, 26 October 2007 (2007-10-26), GB, pages 705 - 711, XP055306869, ISSN: 1470-1626, DOI: 10.1530/REP-07-0208, relates to follistatin serum concentrations during full-term labour in women, and the variations thereof between spontaneous and induced labour.

[0011] P. SREEKANTHREDDY ET AL: "Identification of Potential Serum Biomarkers of Glioblastoma: Serum Osteopontin Levels Correlate with Poor Prognosis", CANCER EPIDEMIOLOGY, BIOMARKERS AND PREVENTION., vol. 19, no. 6, 1 June 2010 (2010-06-01), US, pages 1409 - 1422, XP055306880, ISSN: 1055-9965, DOI: 10.1158/1055-9965.EPI-09-1077, relates to potential serum biomarkers of glioblastoma.

[0012] D F ZHANG ET AL: "Expression of activin A and follistatin in glioblastoma and their effects on U87 in vitro", THE JOURNAL OF INTERNATIONAL MEDICAL RESEARCH, 1 July 2010 (2010-07-01), England, pages 1343 - 1353, XP055306883, Retrieved from the Internet <URL:http://imr.sagepub.com/content/38/4/1343.full.pdf> [retrieved on 20160928], relates to the expression of activin A and follistatin in glioblastoma and their effects on U87 in vitro.

[0013] US20120064529A1 (Predictive Biosciences, Inc.) relates to methods for detecting a target nucleic acid and a target protein in a single assay.

[0014] POUNEH KERMANI ET AL: "BDNF: A Newly Described Mediator of Angiogenesis", 1 May 2007 (2007-05-01), XP055392322, Retrieved from the Internet <URL:https://www.ncbi.nim.nih.gov/pmc/articles/PMC2268985/pdf/nihms-23333.pdf> [retrieved on 20170719], relates to a mediator of angiogenesis.

[0015] XIN ZHOU ET AL: "Conceptual and methodological issues relevant to cytokine and inflammatory marker measurements in clinical research", PUBLISHED IN FINAL EDITED FORM AS: CURR OPIN CLIN NUTR METAB CARE, 1 September 2010 (2010-09-01), pages 541 - 547, XP055756364, Retrieved from the Internet <URL:https://www.ncbi.nim.nih.gov/pmc/articles/PMC2955626/pdf/nihms243735.pdf> [retrieved on 20201203], DOI: 10.1097/MCO, relates to conceptual and methodological issues relevant to cytokine and inflammatory marker measurements in clinical research.

[0016] LENG S X ET AL: "ELISA and multiplex technologies for cytokine measurement in inflammation and aging research", vol. 63, no. 8, 1 August 2008 (2008-08-01), pages 879 - 884, XP008154409, ISSN: 1079-5006, Retrieved from the Internet <URL:http://biomedgerontology.oxfordjournals.org/content/63/8/879.abstract> DOI: 10.1093/GERONA/63.8.879, relates to ELISA and multiplex technologies for cytokine measurement in inflammation and aging research.

[0017] LUNDBLAD R: "ISPUB Considerations for the Use of Blood Plasma and Serum for Proteomic Analysis", THE INTERNET JOURNAL OF GENOMICS AND PROTEOMICS, 1 January 2003 (2003-01-01), XP055756353, Retrieved from the Internet URL:https://print.ispub.com/api/0/ispub-article/3649, relates to ISPUB considerations for the use of blood plasma and serum for proteomic analysis.

[0018] It is therefore an object of the present invention to solve at least one of the problems inherent with the prior art. Another object is to provide a simple, reliable, and cost-effective point-of-care diagnostic method that requires minimal human resource and skill to operate, is non-time consuming, and which facilitates rapid determination of malignancy/benignity of tumours with a reasonably high degree of accuracy.

SUMMARY OF THE INVENTION



[0019] According to an aspect, the present invention provides a method of diagnosing glioma in a subject as set forth in appended claim 1. This method comprises assaying a blood plasma sample of the subject in respect of two or more biomarkers selected from the group consisting of Angiopoietin, Follistatin, HGF, IL-8, Leptin, PDGF-BB, PECAM-1, PDGF-AA, sHER2 neu, sIL-6R alpha, prolactin, sVEGFR1, G-CSF, and FGF, wherein one of the two or more biomarkers is prolactin; and correlating elevated or reduced levels of each of the two or more biomarkers, whether relative to a predetermined threshold or relative to each other, with a determination of the presence of glioma in the subject.

[0020] According to an aspect, the present invention provides a diagnostic system for diagnosing glioma in a subject as set forth in appended claim 11. This diagnostic system comprises: a device configured to receive a blood plasma sample from the subject and configured to assay the blood plasma sample in respect of the two or more biomarkers defined in respect of the aforementioned method of diagnosing glioma; and a computer configured to correlate or facilitate correlation of the amounts of the two or more biomarkers within the blood plasma sample with a determination of the presence of glioma in the subject, wherein the computer is configured to carry out the step of correlating elevated or reduced levels of each of the two or more biomarkers, whether relative to a predetermined threshold or relative to each other, with a determination of the presence of glioma in the subject, as defined in the aforementioned method of diagnosing glioma.

BRIEF DESCRIPTION OF THE DRAWINGS



[0021] 

Figures 1 to 7 show graphical representations of the "control mean" (light grey) and "glioma mean" (dark grey), and also error bars, in relation to IL-8, Angiopoietin, Follistatin, HGF, Leptin, PDGF-BB, and PECAM-1 respectively.

Figures 7A to 7F show graphical representations of the "control mean" (dark grey - left), "low grade glioma mean" (light grey - middle), and "high grade glioma mean" (medium grey - right) and also error bars, in relation to FGF, G-CSF, sHER2neu, sIL-6Ralpha, Prolactin, and sVEGFR1 respectively.

Figure 8 is a scatter-graphical correlation chart for PECAM-1 and PDGF-BB showing the relationship between PECAM-1 and PDGF-BB levels in the 50 glioma patients, and demonstrating a degree of linearity and a correlation coefficient of 0.45.

Figures 8A-8G shows photographic immunohistochemical comparisons between glioma and non-cancerous brain tissues, namely: a) glioma tumour section x40 magnification showing positively staining and non-staining tumour cells; b) glioma tumour section x40 magnification showing negatively staining blood vessels; c) non-cancerous brain tissue x40 magnification showing negatively staining blood vessel; d) glioma tumour section x40 magnification showing interstitial staining; e) glioma tumour section x40 magnification showing interstitial staining, particularly of axonal tracts; f) non-cancerous brain tissue x40 magnification showing negatively staining blood vessel; g) choroid plexus tissue showing positive cytoplasmic staining.


DETAILED DESCRIPTION OF THE INVENTION


Definitions



[0022] Unless otherwise stated, the following terms used in the specification and claims have the following meanings set out below.

[0023] Herein, "diagnosis" generally includes a determination of the presence of glioma.

[0024] Herein, "plasma" refers to the straw-colored/pale-yellow liquid component of blood that normally holds the blood cells in whole blood in suspension. It makes up about 55% of total blood volume. It is the intravascular fluid part of extracellular fluid (all body fluid outside of cells). It is mostly water (93% by volume) and contains dissolved proteins (major proteins are fibrinogens, globulins and albumins), glucose, clotting factors, mineral ions (Na+, Ca++, Mg++, HCO3- Cl- etc.), hormones and carbon dioxide (plasma being the main medium for excretory product transportation). It is to be noted that, for plasma samples, both EDTA plasma and citrate plasma are suitable, whereas heparin plasma is less preferred, since this can absorb certain cytokines.

[0025] "Cytokines" are well known in the art as cell-signaling protein molecules that are secreted by numerous cells and are a category of signaling molecules used extensively in intercellular communication. Cytokines can be classified as proteins, peptides, or glycoproteins; the term "cytokine" encompasses a large and diverse family of regulators produced throughout the body by cells of diverse embryological origin. Some "cytokines" may also be considered "angiogenesis factors", and visa versa.

[0026] "Angiogenesis Factors" are well known in the art as angiogenic growth factors. In the context of the present invention, "cytokines" are generally considered collectively with "angiogenesis factors" given their combined service as biomarkers for glioma, as demonstrated in the Examples and throughout the specification.

[0027] Herein, references to an "assay" or "assaying" includes any form of analysis, including standard biological assays (e.g. bioassays, immunoassays, etc.).

[0028] As used herein, a "subject" refers to an animal, preferably a mammal. In preferred embodiments, the subject is a human subject. In other embodiments, the subject is a non-human mammal, including but are not limited to, dog, cat, horse, etc.

Proliferative Disorder - Glioma



[0029] The methods and diagnostic systems of the present invention pertain to glioma.

[0030] The three main types of malignant glioma are astrocytomas, ependymomas and oligodendrogliomas. The diagnostic methods of the invention may apply to all these types of glioma. A tumour with a mixture of the histological features present in the main three is known as a mixed glioma, which the present invention may also serve to diagnose. The table below shows the sub-types of high grade and low-grade gliomas.
General Tumour Grade WHO Grade Grade Sub-type
Low Grade I Pilocytic astrocytoma
II Oligodendroglioma
II Astrocytoma
High Grade III Anaplastic astrocytomas
III Oligodendrogliomas
IV Glioblastoma multiforme


[0031] In a particular embodiment, the glioma is either a low grade or high grade glioma. In a particular embodiment, the glioma is any one of Pilocytic astrocytoma, Oligodendroglioma, Astrocytoma, Anaplastic astrocytomas, Oligodendrogliomas, Glioblastoma multiforme glioma sub-types.

[0032] In a particular embodiment, the glioma is a Grade III or Grade IV glioma.

Subjects (Patients)



[0033] The subject is suitably an animal, preferably a mammal. In preferred embodiments, the subject is a human subject. In other embodiments, the subject is a non-human mammal, including but are not limited to, dog, cat, horse, etc.

[0034] The subject suitably has or is suspected as having glioma.

[0035] The subject is suitably a glioblastoma or a gliosarcoma patient. In a particular embodiment, the subject is a glioblastoma patient.

Blood Plasma Sample



[0036] In the context of the methods and diagnostic systems of the present invention, a blood plasma sample is used.

Cytokines and Angiogenesis Factors



[0037] In the context of the methods and diagnostic systems of the present invention, the two or more biomarkers are selected from the group consisting of Angiopoietin, Follistatin, HGF, IL-8, Leptin, PDGF-BB, PECAM-1, PDGF-AA, sHER2 neu, sIL-6R alpha, prolactin, sVEGFR1, G-CSF, and FGF, wherein one of the two or more biomarkers is prolactin. Such biomarkers are cytokines and/or angiogenesis factors.

[0038] All the abovementioned abbreviations are outlined below. In any event, all of the abovementioned cytokines and angiogenesis factors are well known in the art without further elaboration, and are available commercially or in assay kits.

Analysis of Blood Plasma Sample - Diagnosis



[0039] The methods of diagnosing glioma in a subject, as described herein, all involve analysis of a blood plasma sample in respect of the aforesaid two or more biomarkers.

Assaying a Blood Plasma Sample



[0040] Assaying the blood plasma sample suitably involves determining the levels of the two or more biomarkers within the blood plasma sample.

[0041] The levels (or calibrated/normalised levels) of the two or more biomarkers may be assessed, for instance, against a predetermined threshold (e.g. determined by prior studies of cytokine/angiogenesis factor levels in blood plasma samples of a representative cross-section of subjects with and without glioma) for each of the two or more biomarkers or relative to each other (e.g. comparing the relative levels/profile of the cytokines/angiogenesis factors concerned). Such an assessment may then be correlated with a diagnosis. In particular, observation of elevated or reduced levels of each of the two or more biomarkers, whether relative to a predetermined threshold or relative to each other, may be correlated with a glioma diagnosis.

[0042] In a particular embodiment, the blood plasma sample(s) are assayed with an immunoassay, for instance based on an antigen-antibody response.

[0043] Assaying the blood plasma sample may involve any suitable assay known in the art. Each of the two or more biomarkers may be assayed for individually, optionally in series. As such, a blood plasma sample may be split into multiple aliquots for testing. Alternatively, each of the two or more biomarkers may be assayed in parallel (e.g. as multiple aliquots). Alternatively, each of the two or more biomarkers may be assayed in parallel in the sample assay (i.e. with a single blood plasma sample), for instance via a multiplex assay.

[0044] In a particular, the blood plasma sample(s) are assayed using a magnetic bead-based multiplex assay designed to measure multiple cytokines and/or angiogenesis factors. The multiplexing feature makes it possible to quantitate the level of multiple proteins in a single well, in just 3 hrs, using as little as 12.5 µl of plasma. Suitable assay kits include the Bio-Plex and Bio-Plex Pro systems, which incorporate magnetic beads into their design. The magnetic beads allow for the option of using magnetic separation during wash steps instead of vacuum filtration. Magnetic separation allows for greater automation without significant alterations to the standard Bio-Plex assay protocol.

[0045] The assay suitably employs a plurality of fluorescently dyed beads (e.g. xMAP technology) to simultaneously detect multiple cytokines and/or angiogenesis factors in a single assay (e.g. a single well). As such, two or more biomarkers may be the subject of analysis. In a particular embodiment, the up to 100 unique fluorescently dyed beads are used for cytokine/angiogenesis factor detection.

[0046] The assay suitably employs a flow cytometer with two lasers and associated optics to measure the different cytokines/angiogenesis factors bound to the surface of the beads.

[0047] The assay suitably employs a diagnostic kit with a (high-speed) digital signal processor that efficiently manages the fluorescent data.

[0048] The bead-based assays suitably operate in a manner similar to a capture sandwich immunoassay. For instance, an antibody directed against the desired cytokine and/or angiogenesis factor targets is suitably covalently bound to internally dyed beads. During the assay, the beads are suitably contacted with the relevant blood plasma sample to facilitate reaction between the covalently bound antibody and the target cytokines and/or angiogenesis factors. After a sufficient contact time, the beads are suitably washed (optionally several times) to remove unbound protein. Thereafter, a biotinylated detection antibody specific to an epitope different from that of the capture antibody is suitably added to the bead reaction mixture. This suitably produces a sandwich of antibodies around the cytokine/angiogenesis factor targets. A reporter complex (e.g. streptavidin-phycoerythrin (streptavidin-PE)) is then suitably added to bind to the biotinylated detection antibodies on the bead surface.

[0049] Data is suitably acquired from the bead reaction mixture using a suitable reader system. In a particular embodiment, the data is acquired using the Bio-Plex system (or Luminex system), a dual-laser, flow-based microplate reader system. The bead reaction mixture is suitably drawn up into the reader system. Lasers and associated optics suitably detect the internal fluorescence of the individual dyed beads as well as the fluorescent reporter signal on the bead surface. This suitably identifies each assay and reports the level of cytokine/angiogenesis factor target in the sample. Intensity of fluorescence detected on the beads indicates the relative quantity of target cytokines and/or angiogenesis factor molecules in the tested samples. A digital processor suitably manages the data output, which is suitably further analyzed and presented as fluorescence intensity (FI) and target concentration data, potentially using Bio-Plex Manager software.

[0050] The levels of the two or more biomarkers can then be used to determine a glioma diagnosis, as described above, whether manually or automatically (i.e. through the data being directly processed by a computer as defined herein).

Diagnostic System



[0051] The present invention provides a diagnostic system for diagnosing glioma in a subject. This diagnostic system is defined hereinbefore and is as set forth in appended claim 11. This diagnostic system comprises: a device configured to receive a blood plasma sample from the subject and configured to assay the blood plasma sample in respect of two or more biomarkers defined in respect of the method of diagnosing glioma of the present invention; and a computer configured to correlate or facilitate correlation of the amounts of the two or more biomarkers within the blood plasma sample with determination of the presence of glioma in the subject, wherein the computer is configured to carry out the step of correlating elevated or reduced levels of each of the two or more biomarkers, whether relative to a predetermined threshold or relative to each other, with a determination of the presence of glioma in the subject, as defined in the method of diagnosing glioma.

[0052] Suitably the device for correlating or facilitating correlation of the results comprises the computer or is in communication with the computer (e.g. whether wired or wireless).

EXAMPLE - Assay of a Blood Plasma Sample



[0053] In the present example, cytokine and angiogenesis factor assays were performed upon blood plasma samples using the magnetic bead-based multiplex assays provided by a Bio-Plex Pro Assay kit. All the relevant protocols, which were duly followed in the present example, are set forth in the Instruction Manual entitled "Bio-Plex Pro Assays Cytokine, Chemokine, and Growth Factors Instruction Manual" available from Bio-Rad Laboratories, Inc at the website www.bio-rad.com, and in particular at http://www.bio-rad.com/webroot/web/pdf/lsr/literature/10014905.pdf. The protocols of this Instruction Manual were followed in relation to "Bio-Plex Pro Human, Mouse, and Rat Cytokine Assays". The Bio-Plex system was prepared as described in the Instruction Manual, suitably calibrated, and validated as described. The magnetic beads present in the 96-well Bio-Plex Pro flat-bottom plates were washed via magnetic separation using the magnetic setting of the Bio-Plex Pro wash station. The 96-well Bio-Plex Pro flat-bottom plates were laid out appropriately, with wells assigned appropriately. Appropriate standards, supplied with the Bio-plex system, were prepared in accordance with the Protocols set forth in the Instruction Manual.

[0054] As described in the Instruction Manual, The Bio-Plex suspension array system is built around the three core elements of xMAP technology:
  • Fluorescently dyed microspheres (also called beads), each with a distinct color code or spectral address to permit discrimination of individual tests within a multiplex suspension. This allows simultaneous detection of more than 100 different types of molecules in a single well of a 96-well microplate
  • A dedicated flow cytometer with two lasers and associated optics to measure the different molecules bound to the surface of the beads
  • A high-speed digital signal processor that efficiently manages the fluorescence data


[0055] Bio-Plex Pro cytokine, chemokine, and growth factor assays are essentially immunoassays formatted on magnetic beads. The assay principle is similar to that of a sandwich ELISA (Figure 1). Capture antibodies directed against the desired biomarker are covalently coupled to the beads. Coupled beads react with the sample containing the biomarker of interest. After a series of washes to remove unbound protein, a biotinylated detection antibody is added to create a sandwich complex. The final detection complex is formed with the addition of streptavidin-phycoerythrin (SA-PE) conjugate. Phycoerythrin serves as a fluorescent indicator, or reporter.

[0056] As also explained in the Instruction Manual, data from the reactions are acquired using a Bio-Plex system or similar_Luminex-based reader. When a multiplex assay suspension is drawn into the Bio-Plex 200 reader for example, a red (635 nm) laser illuminates the_fluorescent dyes within each bead to provide bead classification and_thus assay identification. At the same time, a green (532 nm) laser excites PE to generate a reporter signal which is detected by a photomultiplier tube (PMT). A high-speed digital processor manages data output and Bio-Plex Manager software presents data as Median Fluorescence Intensity (MFI) as well as concentration (pg/mL). The concentration of analyte bound to each bead is proportional to the median fluorescence intensity (MFI) of reporter signal.

[0057] The Instruction Manual summarises the initial preparation for the assays as follows:
  1. 1. Plan the plate layout
  2. 2. Start up/warm up the Bio-Plex system (up to 30 min)
    • Meanwhile, equilibrate assay reagents to room temperature (RT)
    • Begin to thaw samples
  3. 3. Prime wash station or calibrate vacuum manifold
  4. 4. Calibrate the system (now, or later during an incubation)
  5. 5. Reconstitute a single vial of standards in 500 µl of the appropriate diluent, vortex and incubate on ice (30 min)
    • For serum and plasma samples (as per the present example), use Bio-Plex standard diluent
  6. 6. Prepare the 8 point standard dilution series and blank.
    • Add 72 µl diluent to tube S1, and 150 µl diluent to tubes S2-8 and blank.
    • Transfer 128 µl reconstituted standard into S1
    • Then serially dilute 4 fold from S1 thru S8 by transferring 50 µl between tubes. Vortex between transfers
  7. 7. Once thawed, prepare 1x samples
    • Dilute serum, plasma and lysates in Bio-Plex sample diluent
  8. 8. Prepare 1x coupled beads in assay buffer, protect from light
    • From 10x stock: Add 575 µl beads to 5,175 µl buffer
    • From 20x stock: Add 288 µl beads to 5,472 µl buffer
  9. 9. Make sure samples and standards are at RT before dispensing


[0058] The Instruction Manual summarises the running of the assays as follows:
  1. 1. Prewet filter plate with 100 µl assay buffer (skip for flat bottom)
  2. 2. Add 50 µl of 1x beads to the assay plate
  3. 3. Wash 2 times with 100 µl wash buffer
  4. 4. Add 50 µl samples, standards, blank, controls
  5. 5. Cover and incubate in the dark at RT with shaking at 300 RPM
    • 30 min - Human Group I,II and Mouse Group I,II
      With 10 min remaining, prepare 1x Detection Ab in detection antibody diluent.
    • From 10x stock: Add 300 µl Ab to 2,700 µl diluent
    • From 20x stock: Add 150 µl Ab to 2,850 µl diluent
  6. 6. Wash 3 times with 100 µl wash buffer
  7. 7. Add 25 µl of detection antibody
  8. 8. Cover and incubate in the dark at RT with shaking at 300 RPM
    • 30 min - Human Group I,II; Mouse Group I,II
    Meanwhile, prepare software protocol; enter normalized standard S1 values With 10 min remaining, prepare 1x SA-PE in assay buffer, From 100x stock:
    Add 60 µl SA-PE to 5,940 µl assay buffer. Protect from light
  9. 9. Wash 3 times with 100 µl wash buffer
  10. 10. Add 50 µl of strepavidin-PE
  11. 11. Cover and incubate in the dark at RT with shaking at 300 RPM
    • 10 min - Human Group I,II; Mouse Group I,II
  12. 12. Wash 3 times with 100 µl wash buffer
  13. 13. Resuspend beads in 125 µl assay buffer, shake at 1100 RPM for 30 sec
  14. 14. Read plate
    • Low PMT (Low RP1) - Human group I,II; Mouse group I,II


[0059] In accordance with the Instruction Manual, the reagents supplied with the Bio-Plex Pro assay kits for human, mouse, and rat cytokine assays include (Table 1):



[0060] In accordance with the Instruction Manual, the testable cytokines include (Table 2):



[0061] However, additional cytokines and angiogenesis factors were in fact tested, and the relevant standards and protocols developed accordingly. These additional cytokines and angiogenesis factors are detailed in the results section.

Whole Blood Sampling



[0062] Whole blood samples were collected from 50 glioma patients and 27 healthy subjects.

Preparation of Blood Plasma Samples from the Whole Blood Samples



[0063] Blood plasma samples for each of the 50 glioma patients and 27 healthy subjects were prepared by adding the corresponding fresh whole blood sample to a tube containing an anticoagulant, and spinning the tube at 13,200 rpm for 10 min at 4°C until the blood cells fell to the bottom of the tube to clear the samples of precipitate. The blood plasma was then poured or drawn off. The resulting blood plasma had a density of approximately 1025 kg/m3, or 1.025 kg/l. The blood plasma samples were then either assayed immediately or otherwise aliquoted and stored in single use aliquots at -70°C for later use, though repeated freeze/thaw cycles were avoided.

[0064] Before conducting the assays, 1 volume of plasma sample was diluted with 3 volumes of sample diluents (for example, 50 µL sample + 150 µL sample diluents).

Preparation of Coupled Beads



[0065] The preparation of coupled beads is now described using the protocols espoused in the Bio-Plex Pro instruction manual.

[0066] One tube of coupled beads is included with each kit. Instructions are provided for diluting the coupled beads to a 1x concentration.

[0067] When using 10-pack reagents, ensure that only the required volumes of coupled beads, detection antibodies, streptavidin-PE, and buffers have been removed from the tubes or bottles. For example, transfer a one-time volume of assay buffer, sufficient to perform all steps of the assay procedure (that is, prewetting the filter plate, diluting coupled beads, diluting streptavidin-PE, and resuspending the beads) into a 50 ml reservoir.
  1. 1. Use the Calculation Worksheet shown below to calculate the volume of coupled beads and assay buffer needed.
  2. 2. Add the required volume of assay buffer to a 15 ml polypropylene tube.
  3. 3. Vortex the coupled beads at mid speed for 30 sec. Carefully open the cap and pipet any liquid trapped in the cap back into the tube. This is important to ensure maximum bead recovery. Do not centrifuge the vial; doing so will cause the beads to pellet.
  4. 4. Pipet the required volume of stock coupled beads into the 15 ml tube containing assay buffer to dilute the coupled beads to a 1x concentration. Each well requires either 5 µl coupled beads (10x) or 2.5 µl coupled beads (20x) adjusted to a final volume of 50 µl using assay buffer. Refer to the example bead calculations in Tables 3-6 below, which include a 20% excess to compensate for transfer loss.







  5. 5. Protect the beads from light with aluminum foil. Equilibrate at room temperature for 20 min prior to use.

Magnetic bead-based multiplex assay



[0068] The assays were then run as described in the Bio-Plex Pro instruction manual (as also set forth below).

[0069] Bring all buffers, diluted standards, diluted coupled beads, and samples to room temperature prior to use. To ensure optimal performance, pipet carefully (avoiding bubbles) with a calibrated pipet, and use new pipet tips.

[0070] Add Coupled Beads, Standards, and Samples and then:
  1. 1. Cover unused wells with sealing tape.
  2. 2. Prewet the filter plate.
  3. 3. Vortex the diluted coupled beads for 30 sec at medium speed.

    Pour the diluted coupled beads into a reagent reservoir and add 50 µl to each well.

    TIP: A multichannel pipet is highly recommended for ease of use and efficiency.

  4. 4. Wash the wells twice with the wash method of choice.
  5. 5. Gently vortex the diluted standards, blanks, samples, and controls (if applicable) for 1-3 sec. Add 50 µl diluted standard, control, or sample to each well, changing the pipet tip after every volume transfer.
  6. 6. Incubate on shaker at room temperature as specified in Table 7 below.



[0071] Prepare and Add Detection Antibodies.

[0072] One tube of detection antibodies is included with each kit. Instructions are provided for diluting the detection antibodies to a 1x concentration.
  1. 1. While the samples are incubating, use the Calculation Worksheet shown below to calculate the volume of detection antibodies and detection antibody diluent needed. Detection antibodies should be prepared 10-15 min before use.
  2. 2. Add the required volume of detection antibody diluent to a 15 ml tube.
  3. 3. Vortex the detection antibodies for 15-20 sec at medium speed, then perform a 30 sec spin to collect the entire volume at the bottom of the vial.
  4. 4. Pipet the required volume from each detection antibody tube into a 15 ml polypropylene tube. Each well of the assay requires either 2.5 µl detection antibody (10x) or 1.25 µl detection antibody (20x) adjusted to a final volume of 25 µl.


[0073] Refer to the example detection antibody calculations in Tables 8-11 beow. These calculations include a 25% excess to compensate for transfer loss.

[0074] Tables 8-11 summarize the volumes required to prepare 1x detection antibodies from a single 10x or 20x stock. Also shown are volumes to prepare 1x antibodies when mixing two 10x or two 20x stocks. For instructions on preparing 1x antibodies from two stocks at different concentrations (for example when mixing human diabetes (20x) with human group I assays (10x), refer to the Bio-Plex Pro diabetes instruction manual (bulletin #10010747).







5. After incubating the samples, slowly remove and discard the sealing tape.

6. Wash three times with the wash method of choice.

7. Vortex the diluted detection antibodies gently for 1-3 sec. Pour the diluted detection antibodies into a reagent reservoir and add 25 µl to each well using a multichannel pipet.

8. Cover the plate with a new sheet of sealing tape and seal the wells. Incubate on shaker at room temperature as specified in Table 12 below.



[0075] Prepare and Add Streptavidin-PE
  1. 1. While the detection antibodies are incubating, use the Calculation Worksheet shown below to calculate the volume of streptavidin-PE (100x) and assay buffer needed. Each well requires 0.5 µl streptavidin-PE (100x) adjusted to a final volume of 50 µl with assay buffer. Streptavidin-PE should be prepared 10 min before use.
  2. 2. Add the required volume of assay buffer to a 15 ml tube.
  3. 3. Vortex the streptavidin-PE tube for 15-20 sec at medium speed. Perform a 30 sec spin to collect the entire volume at the bottom of the vial.
  4. 4. Pipet the required volume of streptavidin-PE into a 15 ml polypropylene tube containing assay buffer to dilute the streptavidin-PE to a 1x concentration.
    Table 13 nelow shows an example calculation to dilute streptavidin-PE, which includes a 25% excess to compensate for transfer loss. Protect the streptavidin-PE from light until ready to use.

  5. 5. After detection antibody incubation, slowly remove and discard the sealing tape.
  6. 6. Wash three times with the wash method of choice.
  7. 7. Vortex the diluted streptavidin-PE at medium speed for 3-5 sec. Pour the diluted streptavidin-PE into a reagent reservoir and add 50 µl to each well using a multichannel pipet.
  8. 8. Incubate on shaker at room temperature for the specified time shown in Table 14 below.

  9. 9. After the streptavidin-PE incubation step, slowly remove and discard the sealing tape.
  10. 10. Wash the wells three times with the wash method of choice.
  11. 11. Add 125 µl assay buffer to each well. Cover the plate with a new sheet of sealing tape. Shake the plate at room temperature at 1,100 rpm for 30 sec and slowly remove the sealing tape. Ensure that the plate cover has been removed before placing the plate on the reader.

Reading the assay plate



[0076] Assay plates were read in accordance with the Instruction Manual, as described below.

[0077] Bio-Plex Manager software is recommended for all Bio-Plex Pro assay data acquisition and analysis. Instructions for Luminex xPONENT software are also included. For instructions using other xMAP system software packages, contact Bio-Rad Technical Support or your regional Bio-Rad field applications specialist.

[0078] The protocol should be prepared in advance so that the plate is read as soon as the experiment is complete. A protocol file specifies the analytes used in the reading, the plate wells to be read, sample information, the values of standards and controls, and instrument settings.

[0079] Protocols may be obtained from within Bio-Plex Manager software version 6.0 or created from the File menu. Bio-Plex Manager software version 6.0 contains protocols for most Bio-Plex assays. The protocols should be chosen of new protocols should be created.

[0080] Protocols are prepared via the following steps:
  1. 1. Describe protocol and enter information about the assay.
  2. 2. Select analytes (from Table 2 above).
  3. 3. Format the plate according to the Plate Layout template created for the assay.
  4. 4. Enter details of the standards - e.g. highest concentration of each analyte, dilution factors, lot numbers, etc.
  5. 5. Enter controls information, including concentration and dilution information for each user-specified control for each assay.
  6. 6. Enter sample information, including the appropriate dilution factor.
  7. 7. Run the software protocols appropriate for the analytes concerned.


[0081] Data is acquired via the following steps:
  1. 1. Shaking the assay plate at 1,100 rpm for 30 sec, and visually inspecting plate to eensure that the assay wells are filled with buffer.
  2. 2. Run the protocol to start acquiring data.
  3. 3. Use the "wash between plates" function after each plate run to reduce clogging.


[0082] Data analysis and outlier removal is then performed.

[0083] Outliers are identified as standard data points that do not meet accuracy or precision requirements and should be considered invalid when performing curve fitting. As such, they should be removed to generate a more realistic and accurate standard curve. This may result in an extended assay working range and allow quantitation of samples that might otherwise be considered out of range (OOR).

[0084] In Bio-Plex Manager software version 6.0, outliers can be automatically removed by selecting the Optimize button in the Standard Curve window. In Bio-Plex Manager software 6.0 and earlier versions, outliers also can be manually selected in the Report Table.

Calculations



[0085] The Bio-Plex Pro instruction manual details the following calculations:

Plan Plate Layout



[0086] 
  1. 1. Fill out the 96-well plate template (page 43) as instructed in the Plan Plate Layout section (page 13).

    If using either a premixed panel or one singleplex assay, follow these directions.

    Enter the number of wells that will be used in the assay: _ (1)


Calculations for Coupled Beads



[0087] 
  1. 1. Determine the volume of 1x coupled beads needed.
    1. a. Each well requires 50 µl of coupled beads (1x): _ (1) x 50 µl = _ µl (2)
    2. b. Include a 20% excess to ensure enough volume: µl (2) x 0.20 = _ µl (3)
    3. c. Total volume of 1x coupled beads: µl (2) + _ µl (3) = _ µl (4)
    4. d. Volume of 20x coupled beads stock: µl (4)/20 = _ µl (5)
    5. e. Volume of assay buffer required: _ µl (4) - _ µl (5) = _ (6)

Calculations for Coupled Beads



[0088] 
  1. 1. Determine the volume of 1x coupled beads needed.
    1. a. Each well requires 50 µl of coupled beads (1x): _ (1) x 50 µl = _ µl (2)
    2. b. Include a 20% excess to ensure enough volume: µl (2) x 0.20 = _ µl (3)
    3. c. Total volume of 1x coupled beads: µl (2) + _ µl (3) = _ µl (4)
    4. d. Volume of 20x coupled beads stock: µl (4)/20 = _ µl (5)
    5. e. Volume of assay buffer required: _ µl (4) - _ µl (5) = _ (6)

Calculations for Coupled Beads



[0089] 
  1. 1. Determine the volume of 1x coupled beads needed.
    1. a. Each well requires 50 µl of coupled beads (1x): _ (1) x 50 µl = _ µl (2)
    2. b. Include a 20% excess to ensure enough volume: µl (2) x 0.20 = _ µl (3)
    3. c. Total volume of 1x coupled beads: µl (2) + _ µl (3) = _ µl (4)
    4. d. Volume of 20x coupled beads stock: µl (4)/20 = _ µl (5)
    5. e. Volume of assay buffer required: _ µl (4) - _ µl (5) = _ (6)
If mixing singleplex assays, follow these directions.

Calculations for Coupled Beads



[0090] 
  1. 1. Determine the volume of 1x coupled beads needed.

    a. Each well requires 50 µl coupled beads (1x): _ (1) x 50 µl = _ µl (2)

    b. Include 20% excess to ensure enough volume: _ µl (2) x 0.20 = _ µl (3)

    c. Total volume of 1x coupled beads: _ µl (2) + _ µl (3) = _ µl (4)

    d. Enter the number of diabetes single set (or analytes) tubes that will be multiplexed = _ (5)

    e. Volume of 20x coupled beads required from each coupled beads tube: _ µl (4) / 20 = _ µl (6) f. Total volume of diabetes bead stock required: (5) x _ µl (6) = _ µl (7)

    g. Volume of assay buffer required: _ µl (4) - _ µl (7) = _ µl (8)


Calculations for Detection Antibodies



[0091] 2. Determine the volume of 1x detection antibody needed.
  1. a. Each well requires 25 µl detection antibodies (1x): _ (1) x 25 µl = _ µl (9)
  2. b. Include a 25% excess to ensure enough volume: _ µl (9) x 0.25 = _ µl (10)
  3. c. Total volume of 1x detection antibodies: _ µl (9) + _ µl (10) = _ µl (11)
  4. d. Enter the number of diabetes single set (or analytes) tubes that will be multiplexed = _ (5)
  5. e. Volume of 20x detection antibodies required from each detection antibody tube: _ µl (11) / 20 = _ µl (12)
  6. f. Total volume of diabetes detection antibody stock: _ µl (12) x _ (5) = _ µl (13)
  7. g. Volume of detection antibody diluent required: _ µl (11) - _ µl (13) = _µl (14)

Calculations for Streptavidin-PE



[0092] 3. Determine the volume of 1x streptavidin-PE needed.
  1. a. Each well requires 50 µl streptavidin-PE (1x): _ (1) x 50 µl = _ µl (15)
  2. b. Include 25% excess to ensure enough volume: _ µl (15) x 0.25 = _ µl (16)
  3. c. Total volume of 100x streptavidin-PE: _ µl (15) + _ µl (16) = _ µl (17)
  4. d. Volume of 100x streptavidin-PE required: _ µl (17) / 100 = _ µl (18)
  5. e. Volume of assay buffer required: _ µl (17) _ µl (18) = _ µl (19)

Processing of Data



[0093] The blood plasma samples from the 50 glioma patients and 27 healthy subjects were all assayed against various cytokines and angiogensis factors, and the levels of said cytokines and angiogensis factors determined in each case. A mean value for the cytokine and angiogensis factor levels for the 50 glioma patients ("Glioma Mean") and a mean value for the cytokine and angiogensis factor levels for the 27 healthy subjects ("Control Mean") was produced for each respective cytokine and angiogensis factor that was assayed, and the results compared. A statistical comparison was then made as to the significance of the particular cytokine and angiogensis factor in relation to its capacity to indicate the presence of gliomas.

[0094] Figures 1 to 7 show a graphical representation of the "control mean" (light grey) and "glioma mean" (dark grey), and also error bars, in relation to IL-8, Angiopoietin, Follistatin, HGF, Leptin, PDGF-BB, and PECAM-1 respectively.

[0095] Figures 7A to 7F show graphical representations of the "control mean" (dark grey - left), "low grade glioma mean" (light grey - middle), and "high grade glioma mean" (medium grey - right) and also error bars, in relation to FGF, G-CSF, sHER2neu, sIL-6Ralpha, Prolactin, and sVEGFR1 respectively. These figures demonstrate the applicability of the present invention to both low and high grade gliomas.

[0096] Figure 8 is a scatter-graphical correlation chart for PECAM-1 and PDGF-BB showing the relationship between PECAM-1 and PDGF-BB levels in the 50 glioma patients, and demonstrating a degree of linearity and a correlation coefficient of 0.45. This suggests that considering the relative levels of both PECAM-1 and PDGF-BB may provide a good correlation with a favourable or unfavourable diagnosis in relation to glioma.

Results



[0097] Table 15 below compares the "control mean" concentrations of each assayed cytokine and angiogensis factor with the "glioma mean" concentrations of each assayed cytokine and angiogensis factor, and reports the "significance" of the particular cytokine or angiogensis factor in question (i.e. whether or not said cytokine or angiogensis factor is a suitable biomarker in blood plasma for glioma).
Table 15 - Comparison of "Control Mean" and "Glioma Mean" to determine Significance as a Biomarker for Glioma
Cytokine/Angiogenesis factor Control mean pg/ml Glioma mean pg/ml Significance (P<0.05)
IL-2 2.060434783 2.113 No
IL-4 0.204 0.225 No
IL-6 3.730625 2.6252 No
IL-10 3.113478 5.4772 No
GM-CSF 0 0.8078 No
IFN-γ 7.797391 1.93551 YES
TNF-α 8.53826087 8.5034 No
Angiopoietin 282.3258 195.1382 YES
Follistatin 407.9671 757.4796 YES
HGF 915.6583 1073.045 YES
IL-8 20.13348 16.37449 YES
Leptin 5452.401 9102.635 YES
PDGF-BB 2817.792 4866.84 YES
PECAM-1 2734.137 3832.264 YES
VEGF 64.29167 69.3364 No
       
FGF 184.6 220.2 Yes
G-CSF 379.4 438.4 Yes
sHER2neu 4845.3 3604.8 Yes
slL-6Ralpha 9603.1 12672.6 Yes
Prolactin 8101.9 27827.7 Yes
sVEGFR1 736.6 911 Yes
PDGF AA 7315 8578 Yes


[0098] As will be apparent, at least IFN-γ, Angiopoietin, Follistatin, HGF, IL-8, Leptin, PDGF-BB, PECAM-1, PDGF-AA, sHER2 neu, sIL-6R alpha, prolactin, sVEGFR1, G-CSF, and FGF show a high degree of "significance", though the significance of IFN-γ was treated with caution given that many individuals demonstrated a zero concentration of this particular cytokine. In addition, it was observed that levels of Follistatin are higher in glioma patients than healthy subjects, Interleukin 10 is higher, Angiopoetin is lower, Leptin is higher, and PDGF-BB are higher. These cytokines and angiogenesis factors are therefore clearly excellent candidates as blood plasma biomarkers of gliomas.

[0099] In view of the above disclosure, relevant diagnostic systems and methods can be readily developed, using routine workshop techniques known in the art.

[0100] The above data is further corroborated by immunohistochemical comparisons between glioma brain tissue and non-cancerous brain tissue. Figures 8A-8G shows photographic immunohistochemical comparisons between glioma and non-cancerous brain tissues, namely: a) glioma tumour section x40 magnification showing positively staining and non-staining tumour cells; b) glioma tumour section x40 magnification showing negatively staining blood vessels; c) non-cancerous brain tissue x40 magnification showing negatively staining blood vessel; d) glioma tumour section x40 magnification showing interstitial staining; e) glioma tumour section x40 magnification showing interstitial staining, particularly of axonal tracts; f) non-cancerous brain tissue x40 magnification showing negatively staining blood vessel; g) choroid plexus tissue showing positive cytoplasmic staining.

[0101] Figures 8A-8G show, in particular, immunohistochemical staining of Follistatin, thereby showing an increased accumulation of this protein in the brain tissue of glioma patients.

[0102] Figures 8A-8G show the ability of Follistatin to identify tumour margins during immunohistochemical staining of brain tissue. Some gliomas exhibited significant follistatin immunostaining of tumour cells, many appeared to express gemistocytic morphology. However staining was not uniform throughout the tumour sample and some cells were patently immuno-negative (Fig. a). Positive immunostaining was entirely cytoplasmic with no membrane or nuclear component and other tissue elements within the sections, including blood vessels, were completely negative (Fig. b). There were no specific features of the tumours or constituent cells which were evidently predictive of immunopositivity or to account for the significant variability between individual tumours. The non cancerous (viz. normal) brain tissue was uniformly negative throughout and there was no staining of either neurones or glial cells (Fig c). There was a distinct interstitial stain in the presence of negatively staining cells that followed the axonal tracts of the sections (figs. d and e). There was no specific axonal staining and some of the axonal tracts did not take up any stain. The non-cancerous brain axonal tracts were uniformly negative (fig. f). There was some specific cytoplasmic staining of some cells from the choroid plexus (fig. g). This may suggest that Follistatin is being secreted into the CSF.

Abbreviations



[0103] 

Basic FGF - Basic fibroblast growth factor

G-CSF - Granulocyte-colony stimul.factor

GM-CSF - Granulocyte-macrophage colony stimulating factor

HGF - Hematopoietic growth factors,

ICAM-1 - Intercellular adhesion molec. 1

IFN-gamma - Interferon gamma

IL-1α - Interleukin 1 alpha

IL-1β - Interleukin 1 beta

IL-1ra - Interleukin 1 receptor antagon.

IL-1 R1 - Interleukin 1 receptor-rel.prot 1

IL-1 R4/ST2 - Interleukin 1 receptor 4, ST2

IL-2 - Interleukin 2

sIL-2 Rα - Interleukin 2 soluble receptor α

IL-4 - Interleukin 4

IL-6 - Interleukin 6

IL-6 R - Interleukin 6 receptor

IL-8 - Interleukin 8

IL-10 - Interleukin 10

PDGF AA - Platelet-derived growth factor

PDGF-BB - Platelet-derived growth factor

sHER2 neu - Human Epidermal Growth Factor Receptor 2

sIL-6R alpha - soluble Interleukin-6 receptor alpha

sVEGFR1 - soluble vascular endothelial growth factor receptor 1

TNF-α - Tumor necrosis factor-alpha

TNF-β - Tumor necrosis factor-beta

VEGF - Vascular endothelial growth f.




Claims

1. A method of diagnosing glioma in a subject, the method comprising assaying a blood plasma sample of the subject in respect of two or more biomarkers selected from the group consisting of Angiopoietin, Follistatin, HGF, IL-8, Leptin, PDGF-BB, PECAM-1, PDGF-AA, sHER2 neu, sIL-6R alpha, prolactin, sVEGFR1, G-CSF, and FGF, wherein one of the two or more biomarkers is prolactin; and correlating elevated or reduced levels of each of the two or more biomarkers, whether relative to a predetermined threshold or relative to each other, with a determination of the presence of glioma in the subject.
 
2. The method as claimed in claim 1, wherein the two or more biomarkers include follistatin.
 
3. The method as claimed in claim 1 or claim 2, wherein assaying the blood plasma sample of the subject is performed in respect of three or more biomarkers selected from any one of the groups of claims 1 to 2.
 
4. The method as claimed in any of claims 1 to 2, wherein the method comprises correlating elevated or reduced levels of each of the two or more biomarkers, relative to a predetermined threshold, with a determination of the presence of glioma in the subject.
 
5. The method as claimed in claim 1 or claim 4, wherein correlating the analytical results with a determination of the presence of glioma in the subject involves an initial comparison of the analytical results with a reference standard or with previous analytic results that have been pre-correlated with a determination of the presence of glioma in the subject.
 
6. The method of any of claims 1 to 5, wherein the blood plasma sample is assayed with an immunoassay.
 
7. The method of any of claims 1 to 6, wherein the blood plasma sample is assayed using a magnetic bead-based multiplex assay designed to measure multiple biomarkers.
 
8. The method of claim 7, wherein the assay employs a plurality of fluorescently dyed beads to simultaneously detect multiple biomarkers in a single assay.
 
9. The method according to any preceding claim, wherein the glioma is low grade glioma.
 
10. The method according to any of claims 1 to 8, wherein the glioma is high grade glioma.
 
11. A diagnostic system for diagnosing glioma in a subject, comprising:

a device configured to receive a blood plasma sample from the subject and configured to assay the blood plasma sample in respect of the two or more biomarkers defined in any of claims 1 to 10; and

a computer configured to correlate or facilitate correlation of the amounts of the two or more biomarkers within the blood plasma sample with a determination of the presence of glioma in the subject, wherein the computer is configured to carry out the step of correlating elevated or reduced levels of each of the two or more biomarkers, whether relative to a predetermined threshold or relative to each other, with a determination of the presence of glioma in the subject, as defined in the method of any of claims 1 to 10.


 
12. The diagnostic system of claim 11, wherein the device comprises the computer.
 


Ansprüche

1. Verfahren zum Diagnostizieren eines Glioms bei einem Subjekt, wobei das Verfahren Untersuchen einer Blutplasmaprobe des Subjekts in Bezug auf zwei oder mehr Biomarker, die aus der Gruppe ausgewählt sind, die aus Angiopoetin, Follistatin, HGF, IL-8, Leptin, PDGF-BB, PECAM-1, PDGF-AA, sHER2/neu, sIL-6R alpha, Prolactin, sVEGFR1, G-CSF und FGF besteht, wobei einer der zwei oder mehr Biomarker Prolactin ist; und Korrelieren erhöhter oder erniedrigter Spiegel jedes der zwei oder mehr Biomarker, ob relativ zu einem vorbestimmten Schwellenwert oder relativ zueinander, mit einer Bestimmung des Vorhandenseins eines Glioms bei dem Subjekt umfasst.
 
2. Verfahren nach Anspruch 1, wobei die zwei oder mehr Biomarker Follistatin enthalten.
 
3. Verfahren nach Anspruch 1 oder Anspruch 2, wobei das Untersuchen der Blutplasmaprobe des Subjekts in Bezug auf drei oder mehr Biomarker durchgeführt wird, die aus einer der Gruppen der Ansprüche 1 bis 2 ausgewählt sind.
 
4. Verfahren nach einem der Ansprüche 1 bis 2, wobei das Verfahren Korrelieren erhöhter oder erniedrigter Spiegel jedes der zwei oder mehr Biomarker relativ zu einem vorbestimmten Schwellenwert mit einer Bestimmung des Vorhandenseins eines Glioms bei dem Subjekt umfasst.
 
5. Verfahren nach Anspruch 1 oder Anspruch 4, wobei das Korrelieren der Analyseergebnisse mit einer Bestimmung des Vorhandenseins eines Glioms bei dem Subjekt einen anfänglichen Vergleich der Analyseergebnisse mit einem Referenzstandard oder mit früheren Analyseergebnissen einschließt, die mit einer Bestimmung des Vorhandenseins eines Glioms bei dem Subjekt vorkorreliert wurden.
 
6. Verfahren nach einem der Ansprüche 1 bis 5, wobei die Blutplasmaprobe mit einem Immunassay untersucht wird.
 
7. Verfahren nach einem der Ansprüche 1 bis 6, wobei die Blutplasmaprobe unter Verwendung eines Multiplex-Assays auf Basis von Magnetkügelchen untersucht wird, der zum Messen vielfacher Biomarker ausgelegt ist.
 
8. Verfahren nach Anspruch 7, wobei der Assay eine Vielzahl von fluoreszierend gefärbten Kügelchen einsetzt, um gleichzeitig vielfache Biomarker in einem einzigen Assay nachzuweisen.
 
9. Verfahren nach einem vorhergehenden Anspruch, wobei das Gliom ein niedriggradiges Gliom ist.
 
10. Verfahren nach einem der Ansprüche 1 bis 8, wobei das Gliom ein hochgradiges Gliom ist.
 
11. Diagnostisches System zum Diagnostizieren eines Glioms bei einem Subjekt, umfassend:

eine Vorrichtung, die dazu konfiguriert ist, eine Blutplasmaprobe von dem Subjekt aufzunehmen, und dazu konfiguriert ist, die Blutplasmaprobe in Bezug auf die zwei oder mehr Biomarker, die in einem der Ansprüche 1 bis 10 definiert sind, zu untersuchen; und

einen Computer, der dazu konfiguriert ist, die Mengen der zwei oder mehr Biomarker in der Blutplasmaprobe mit einer Bestimmung des Vorhandenseins eines Glioms bei dem Subjekt zu korrelieren oder eine solche Korrelation zu erleichtern, wobei der Computer dazu konfiguriert ist, den Schritt eines Korrelierens erhöhter oder erniedrigter Spiegel jedes der zwei oder mehr Biomarker, ob relativ zu einem vorbestimmten Schwellenwert oder relativ zueinander, mit einer Bestimmung des Vorhandenseins eines Glioms bei dem Subjekt, wie in dem Verfahren nach einem der Ansprüche 1 bis 10 definiert, auszuführen.


 
12. Diagnostisches System nach Anspruch 11, wobei die Vorrichtung den Computer umfasst.
 


Revendications

1. Procédé de diagnostic d'un gliome chez un sujet, le procédé comprenant l'analyse d'un échantillon de plasma sanguin du sujet vis-à-vis de deux biomarqueurs ou plus choisis dans le groupe constitué de l'angiopoïétine, de la follistatine, du HGF, de l'IL-8, de la leptine, du PDGF-BB, du PECAM-1, du PDGF-AA, du sHER2 neu, du sIL-6R alpha, de la prolactine, du sVEGFR1, du G-CSF et du FGF, dans lequel l'un des deux biomarqueurs ou plus est la prolactine ; et la corrélation de niveaux élevés ou réduits de chacun des deux biomarqueurs ou plus, que ce soit par rapport à un seuil prédéterminé ou les uns par rapport aux autres, avec une détermination de la présence d'un gliome chez le sujet.
 
2. Procédé selon la revendication 1, dans lequel les deux biomarqueurs ou plus comprennent la follistatine.
 
3. Procédé selon la revendication 1 ou la revendication 2, dans lequel l'analyse de l'échantillon de plasma sanguin du sujet est effectuée vis-à-vis de trois biomarqueurs ou plus choisis parmi l'un quelconque des groupes des revendications 1 à 2.
 
4. Procédé selon l'une quelconque des revendications 1 à 2, dans lequel le procédé comprend la corrélation de niveaux élevés ou réduits de chacun des deux biomarqueurs ou plus, par rapport à un seuil prédéterminé, avec une détermination de la présence d'un gliome chez le sujet.
 
5. Procédé selon la revendication 1 ou la revendication 4, dans lequel la corrélation des résultats analytiques avec une détermination de la présence d'un gliome chez le sujet implique une comparaison initiale des résultats analytiques à un étalon de référence ou à des résultats analytiques antérieurs qui ont été pré-corrélés avec une détermination de la présence d'un gliome chez le sujet.
 
6. Procédé selon l'une quelconque des revendications 1 à 5, dans lequel l'échantillon de plasma sanguin est analysé par un immunoessai.
 
7. Procédé selon l'une quelconque des revendications 1 à 6, dans lequel l'échantillon de plasma sanguin est analysé à l'aide d'un essai multiplex à base de billes magnétiques conçu pour mesurer de multiples biomarqueurs.
 
8. Procédé selon la revendication 7, dans lequel l'analyse emploie une pluralité de billes à teintes fluorescentes pour détecter simultanément de multiples biomarqueurs en une seule analyse.
 
9. Procédé selon l'une quelconque des revendications précédentes, dans lequel le gliome est un gliome de bas grade.
 
10. Procédé selon l'une quelconque des revendications 1 à 8, dans lequel le gliome est un gliome de haut grade.
 
11. Système de diagnostic pour diagnostiquer un gliome chez un sujet, comprenant :

un dispositif configuré pour recevoir un échantillon de plasma sanguin du sujet et configuré pour analyser l'échantillon de plasma sanguin vis-à-vis des deux biomarqueurs ou plus définis dans l'une quelconque des revendications 1 à 10 ; et

un ordinateur configuré pour corréler ou faciliter la corrélation des quantités des deux biomarqueurs ou plus dans l'échantillon de plasma sanguin avec une détermination de la présence d'un gliome chez le sujet, dans lequel l'ordinateur est configuré pour effectuer l'étape de corrélation de niveaux élevés ou réduits de chacun des deux biomarqueurs ou plus, que ce soit par rapport à un seuil prédéterminé ou les uns par rapport aux autres, avec une détermination de la présence d'un gliome chez le sujet, tel que défini dans le procédé selon l'une quelconque des revendications 1 à 10.


 
12. Système de diagnostic selon la revendication 11, dans lequel le dispositif comprend l'ordinateur.
 




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Cited references

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